Include federal tax concepts in state tax variables for states that adopt federal ones

[MaxGhenis]

For example, several states adopt federal AGI, standard deduction, itemized deductions, and/or taxable income concepts. In #5436 I skipped those as we need to decide how to handle them. I see three options:

1. Create new variables for them by hand, e.g. a co_agi file with adds = ["adjusted_gross_income"]
2. Create new variables for them in a loop, similar to _generate_state_mfs_variables.py in Add state-level summary tax variables #5436
3. Use a conditional sum in the summary variables like state_agi to use federal concepts in the relevant states, rather than adds